This application claims the priority of German patent document 100 47 751.8, filed Sep. 27, 2000, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a method for the longitudinal control of a vehicle in which information from a navigation system is recorded.
Such a method for longitudinally controlling a vehicle has been known, for example, from German patent document DE 196 38 511 A1. This reference particularly describes speed control systems that select the drive and/or brake systems of a vehicle in such a way that either a target speed or a target distance to the vehicle in front is adjusted. In the method known from DE 196 38 511 A1, such speed control systems are supplied with information from a navigation system that is also installed in the vehicle. For this purpose, for example, a control device that is allocated to the longitudinal control system can have an interface to the navigation system""s electronics.
Familiar longitudinal control systems have so far been designed in such a way that during regular operation the same longitudinal acceleration to the set target speed takes place for all situations when a subsequent trip is terminated and/or when the longitudinal control and/or speed control is turned on (again) from a switched-off state.
The goal of the invention is to perform adjustments to situations on a longitudinal control system of the above-described type while utilizing the information from the navigation system.
This goal is achieved by a method for the longitudinal control of a vehicle in which information from a navigation system is recorded and where, in dependence on the information of the navigation system, a target value of at least one parameter for longitudinal control is determined. Through the information from the navigation system, the probability (w) is determined with which the vehicle will drive onto a highway entrance. A longitudinal acceleration, which is increased in comparison with regular operation, takes place when the probability (w) is higher than a specified threshold. Beneficial embodiments of the invention are the objects of the dependent claims.
Particular focus with regard to the object of the invention is directed at the situation occurring at highway entrances, where a desire by the driver for increased dynamics should be expected.
Based on the invention, the probability (xe2x80x9centering probabilityxe2x80x9d) with which the vehicle will drive on a highway entrance is determined with the information from the navigation system. When the entering probability is higher than a specified threshold (variable or fixed) and the speed control is switched on, a longitudinal acceleration that is higher than would otherwise occur during regular operation takes place. Preferably, a longitudinal acceleration progression is specified, which determines higher longitudinal acceleration as well as a higher longitudinal acceleration gradient in dependence of the vehicle speed.
The map of a navigation system generally consists of a multitude of route segments that are arranged in a tree-shaped diagram. In order to determine the entering probability, the system checks at the beginning of each current defined route segment whether a highway entrance exists and whether the highway entrance is located on the programmed route and/or whether at least one operating parameter of the vehicle indicates a desire on the part of the driver to enter the highway. Such operating parameters are, e.g. actuation of a turn signal or the set vehicle speed. The entering probability will be higher when the driver actuates the turn signal in the typical direction for highway entrances for each respective country (e.g. in Germany, to the left (xe2x80x9cright-hand trafficxe2x80x9d), in England, to the right (xe2x80x9cleft-hand trafficxe2x80x9d)) and/or when the entrance is part of the route programmed in the driver""s navigation system. Furthermore, e.g. a high set vehicle speed also indicates a higher entering probability.
The invented method is preferably integrated into a control device that is already provided for a longitudinal control system. Then, only an interface to the navigation system must be established.
The invented inquiry and processing method for information from the navigation system on current and future context permits adaptive control that is adjusted to the respective situation as well as driver-typical control of the longitudinal dynamics with a longitudinal control system. Functional quality and driving comfort are increased.